Coated abrasive articles generally contain an abrasive material typically in the form of abrasive grains bonded to a backing by means of one or more adhesive layers. Such articles usually take the form of sheets, discs, belts, bands and the like which can be adapted to be mounted on pulleys, wheels or drums. Abrasive articles can be used for sanding, grinding or polishing various surfaces of, for example only, and not by way of limitation, steel and other metals, wood, wood-like laminates, plastic, fiberglass, leather or ceramics.
Coated abrasive articles are used industrially, commercially and by individual consumers to prepare any of a variety of materials for use or for further processing. Exemplary uses of such abrasive products include: preliminary preparation of a surface before priming or painting, cleaning the surface of an object to remove oxidation or debris, and grinding or abraiding an object to obtain a specific shape, to upbraid a surface to clean or facilitate a bonding or coating such as paint, or to provide a desired surface finish especially a smooth or otherwise a decorative finish.
Many abrasive articles are used as discs in grinding assemblies. A typical such abrasive, sanding or grinding assembly includes: a back-up pad or support pad made from a resilient and reinforced material such as rubber or plastic, an abrasive disc which is typically adhesively or hook and loop mounted on the back-up pad, or otherwise secured by appropriate fastening members attached to the abrasive disc, and a rotatable shaft and cap for mounting the abrasive disc and back-up pad to an appropriate electric or air pressure driven power tool. In use, the shaft of the assembly is rotated by the power tool and the abrasive coated surface of the disc is pressed against a work piece with considerable force, thus the disc is subjected to severe stresses.
The backings used in coated abrasive articles are typically made of paper, polymeric materials, cloth, non-woven materials, vulcanized fiber, or combinations of these materials. Many of these materials are not appropriate for certain applications because they are not of sufficient strength, flexibility or impact resistant.
The present invention is directed to coated abrasive finishing articles which utilize fabric or paper as the backing material. Such backing materials when utilized as coated abrasive discs used in a grinding operation such as: weld grinding, contour grinding, and edge grinding it has been found that the backing material, particularly around the outer edges of the disc, tends to deteriorate rather rapidly thus causing a very short useful life for the abrasive disc. The deterioration and short life is contributed to by the limited radial strength of the fabric and/or paper backing
In many instances coated abrasive finishing articles have an additional coating or layer applied to the surface of the backing material opposite that to which the abrasive articles are secured in order to provide additional lifetime to the coated abrasive disc. It has, however, been found that when such additional coating or laminations are applied to the surface of the backing material that the flexibility of the abrasive disc is compromised. That, therefore, results in the inability of the operator to utilize the abrasive disc to abrasively finish surfaces which have curvatures thereto of any significant degree.
Thus there exists a need for a flexible abrasive finishing article which has a tailored cutting ability, a long useful life which can be made in a simple method and does not in anyway compromise the flexibility of the abrasive finishing article. Particularly, such abrasive finishing articles are formed as discs.